MIL-C-18312 Capacitors, Fixed, Metallized \(Paper-Plastic, Or Plastic Film\) Dielectric, Direct Current \(Hermetically Sealed In Metal Cases\), General Specification ForThis specification covers the general requirements for fixed capacitors with metallized \(paper, paper-plastic or plastic film\) dielectric, direct current, hermetically sealed in metal cases. These capacitors should only be used in circuitry in which high values of insulation resistance are not essential, and in which occasional momentary breakdowns can be tolerated.

Pages 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11 - 12 - 13 - 14 - 15 - 16 - 17 - 18 - 19 - 20 - 21 - 22 - 23

MIL-C-18312G

4.7.8 Vibration (see 3.11).

4.7.8.1 Low frequency. Capacitors shall be tested in accordance with method 201 of MIL-STD-202. The following

details and exceptions shall apply:

a. Tests and measurements prior to vibration: Not applicable.

b. Method of mounting: Securely fastened by normal mounting means. Wire-lead capacitors shall be secured

1/2 �1/8 inch from the case.

c. Duration of vibration: 3 hours (60 minutes in each direction).

d. Tests and measurements during vibration: During the last 30 minutes of vibration in each direction, an

electrical measurement shall be made to determine intermittent contacts or open-circuiting or short-

circuiting.

e. Tests and measurements after vibration: Not applicable.

4.7.8.2 High frequency. Capacitors shall be tested in accordance with method 204 of MIL-STD-202. The following

details and exceptions shall apply:

a. Mounting of specimens: Capacitors shall be rigidly mounted by the body to a vibration-test apparatus.

Wire-lead capacitors shall be secured 1/2 �1/8 inch from the case.

b. Test condition letter: B.

c. Duration and direction of motion: 4 hours in each of 3 mutually perpendicular directions (total of 12 hours),

one parallel and the other perpendicular to the cylindrical axis.

d. Measurements during vibration: During the last cycle in each direction, an electrical measurement shall be

made to determine intermittent contacts or open-circuiting or short-circuiting.

e. Measurements after vibration: Not applicable.

4.7.9 Salt atmosphere (corrosion) (see 3.12). Capacitors shall be tested in accordance with method 101 of MIL-

STD-202. The following details and exceptions shall apply:

a. Applicable salt solution: The salt-solution concentration shall be 20 percent.

b. Test condition letter: B.

c. Measurements after exposure: Not applicable.

After the test, capacitors shall be visually examined for evidence of harmful corrosion, unwrapping of, or mechanical

damage to insulating sleeves, and obliteration of marking.

4.7.10 Thermal shock and immersion (see 3.13).

4.7.10.1 Thermal shock. Capacitors and brackets shall be tested in accordance with method 107 of MIL-STD-202,

with the following exceptions:

a. Test condition A shall apply, except that step 3 shall be as specified (see 3.1).

b. No measurements shall be made before or after cycling.